Gas tank leak

[wardad]

So - first decent weather in MA this week and my Kat is garaged, tank off and waiting for the JB weld to cure. Figures.

Anyway, curious to know how people have dealt with tank problems in case the JB doesn't do the trick, keeping in mind that I want to get more riding than waiting in this season.

At a quick glance, my tank looks really good for its age, but once it sprung a leak and forced me to drain, I was able to angle a small flashlight inside and discovered an oval area of rust on the inside left (kickstand side). Before using JB, I sanded down to bare metal on the outside of the tank and found the pinhole. Looks like there is only one, but I assume that it may have friends just below the surface.

I have read up on Kreem, POR 15 from the do it myself angle, and Red Kote and full tank restoration (cut out, blast, re-weld, seal). The DIY seems like a lot of work with good chance of it ending badly - especially with all the recommended prep work.

What have you done? What did you like, and what should be avoided like the plague? Also - if you have any sources for aftermarket (new) tanks for vintage bikes, please post. I couldn't find much on my initial search

[Nessism]

There are tons of threads here on how to derust and seal a tank. I suggest you try the Advanced Search function and limit the search to "titles only".

Once you get the tank derusted I recommend Caswell Plating epoxy. It's thick and is the best material to seal a tank with holes in my opinion.

[wardad]

Thanks - modified the search and found the threads.

For now, Liquid Steel seems to have plugged the hole successfully, so I am going to ride for the rest of the season or until it leaks again. I like the Rust Evaporator/Caswell idea and will probably give it a try in the off season.

[Nessism]

Thanks - modified the search and found the threads.

For now, Liquid Steel seems to have plugged the hole successfully, so I am going to ride for the rest of the season or until it leaks again. I like the Rust Evaporator/Caswell idea and will probably give it a try in the off season.

Adding a fuel filter may help you get though the season. DO NOT get an automotive type fuel filter, this type is too restrictive. You need a filter for a lawn mower or other type of gravity fed fuel system. This type of filter is not the most effective but it's better than just letting that rust flow straight into the carbs.

[mike_of_bbg]

I'm about to go through that myself. Indeed, PM me later and I may be willing to send you the rest of the mix for very little (the Caswell kit coats two tanks). In my research it takes about a week to do it right. After you wash out the tank (there is no need to de-rust it other than large chunks, as they say the epoxy adheres better to a lightly rusty tank) you should wait about 3 days so the tank is BONE DRY before you coat, then let the coat cure for min 3 days before putting gas in it. There are at least 3 tiny holes in my tank so I'm really hoping this does the trick.

[Nessism]

I've read the stuff about how Caswell and Por-15 say you can coat over rust but I don't care, cleaning off the rust with phorphoric acid or Evapo-Rust is the way to go in my experience. If you seal over the rust and the coating gets chipped for some reason, the rust will start to propagate under the coating. Removing the rust eliminates this possibility.

[blizzard]

With this tank coating exactly how do you spread this stuff in order to be sure you coat the whole inside of the tank? Do you somehow seal up the openings and slosh it around?

[mike_of_bbg]

Yes. They recommend taping putty over the holes to ensure it does not escape. I haven't opened the Caswell yet but part A feels really thick when I shake the can.

There are instructions available at the product site:

http://www.caswellplating.com/aids/epoxygas.htm

[argonsagas]

The BEST method is to find a radiator repair shop that does it or, as applies here, find a shop that specializes in gas tank repairs, (gastankrenu) and have them do the work for you, because they do a great job and give a written guarantee on their work. Costs more than Kreem, etc., but more than well worth the price.